Endoscopic Ultrasound-guided Fine-needle Aspiration Research Articles

Evaluation of 18FDG PET-CT-positive mediastinal-hilar lymph nodes in extrathoracic malignancies by EBUS-TBNA; correlation of SUVmax, and short-axis diameter with the final diagnosis.

Intrathoracic lymph node metastasis from extrathoracic neoplasms are rare. Primary malignancies that metastasize to mediastinal-hilar lymph nodes are head and neck , carcinoma breast ,and genitourinary. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)/endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is currently the preferred modality for mediastinal lymph node sampling. Fifty seven patients with extrathoracic malignancies with maximum standardized uptake value (SUVmax) of mediastinal-hilar lymph nodes greater than or equal to 2.5 were taken up for EBUS-TBNA. The histo-cytopathological results obtained from EBUS-TBNA were compared with SUVmax value and short-axis diameter of a lymph node as noted on EBUS. Out of 74 sampled nodes, 49 (66.2%) were benign and 25 (33.8%) were malignant. The SUVmax range of benign nodes was 2.8-13 as compared to 3-18 of malignant nodes. The size range of malignant and benign nodes were 8-35 mm and 8-30 mm, respectively. The mean size of abnormal nodes (metastatic + granulomatous) was 17.5 (8-35 mm) and the mean SUVmax was 9.1 (3.4-18), and it was a statistically significant difference when compared to reactive (normal) nodes. At SUVmax cut-off 7.5, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) were 78.5%, 81.2%, 84.6%, and 74.2%, respectively for detecting abnormal nodes. At 13 mm size cut-off, sensitivity, specificity, PPV, NPV were 75.5%, 65%, 75%, and 72%, respectively, for detecting abnormal nodes. The majority of mediastinal-hilar nodes with increased metabolic activity are benign in nature. Size and SUVmax are poor predictors of metastasis in tuberculosis endemic region. There should be a restrictive attitude toward invasive diagnostic testing for mediastinal-hilar nodes in extrathoracic malignancies.

Endoscopic Ultrasound-Guided Fine-Needle Biopsies to Generate Preclinical Disease Models to Study Inflammation in Pancreatic Ductal Adenocarcinoma.

Patient-derived xenografts (PDXs) are valuable models to study cancer biology, behavior, and response to therapies in vivo. Pancreatic cancer is an aggressive and treatment-resistant disease, and typical biopsies are often of low cellular yield and therefore present challenges for the creation of PDXs. This chapter will describe a method to establish PDX models from tissue biopsies obtained via endoscopic ultrasound-guided fine-needle aspiration, a relatively noninvasive technique which compared to surgery is available to pancreatic cancer patients at all stages of disease. Furthermore, we also describe methods to incorporate "humanization" of PDXs via reconstitution with human immune cells, thus mimicking the immune cell-rich microenvironment of pancreatic tumors.

Endoscopic ultrasound to the rescue of pancoast tumour.

Dear Editor, A 48-year-old male presented with a two-month history of right-sided shoulder pain with right arm radiation and significant weight loss. A radiograph showed an opacity in the right upper zone. A 34 × 45 × 52 mm mass in the apex of the right lung was seen on contrast-enhanced computed tomography (CECT) [Figure 1a]. Magnetic resonance imaging (MRI) for local staging showed involvement of the right subclavian artery and nerve roots [Figure 1b]. A percutaneous biopsy was planned, but no safe window was available due to the clavicle and multiple vessels on the anterior aspect. Because of the proximity of the lesion to the oesophagus, the patient was referred for endoscopic ultrasound (EUS)-guided biopsy. EUS confirmed the findings of prior imaging [Figure 1c]. An initial attempt at EUS-guided fine-needle aspiration (FNA) with 22-G needle failed as the tumour was very hard. Hence, FNA of visualised subcarinal lymph nodes was performed with a 22-G needle followed by FNA of the tumour with a 19-G needle [Figure 2a]. After the procedure, the patient was observed for four hours and was discharged after confirming the absence of pneumothorax on chest radiograph. A final diagnosis of non-small cell carcinoma was made on pathological [Figure 2b] and cytological examination based on visualisation of clusters of large polygonal cells with round-to-oval vesicular pleomorphic nuclei with no evidence of malignancy in the mediastinal nodes. Because of an unresectable lesion, the patient was planned for a combination of induction chemotherapy and radiotherapy.Figure 1: (a) Contrast-enhanced computed tomography (CECT) of thorax showing a mass in the apex of the right lung. (b) Magnetic resonance imaging (MRI) showing involvement of the right subclavian artery (large arrow) and nerve roots of C8, T1, and T2 (small arrows), (c) Transoesophageal endoscopic ultrasound (EUS) showing a hypoechoic irregular lung mass located on top on lung parenchyma (asterisk) and encasing the subclavian artery anteriorly (arrow)Figure 2: (a) Endoscopic ultrasound-guided fine needle aspiration from lung mass, (b) Haematoxylin and eosin (H and E) staining of core lung mass biopsy, suggestive of non-small cell carcinoma of the lung (arrow)EUS has an established role in tissue acquisition from mediastinal lymph nodes, but data on EUS-guided sampling from lung mass remains limited. Transbronchial needle aspiration (TBNA) and endobronchial ultrasound-guided needle aspiration (EBUS-FNA) are the preferred modalities for the diagnosis and staging of lung cancer.[1] However, the tumour’s location at the apex of the lung makes them inaccessible to TBNA or EBUS-FNA. In such cases, tumours close to the oesophagus may be amenable to transoesophageal EUS-guided FNA. It also has the advantage of simultaneous sampling of mediastinal lymph nodes and other organs like the liver and adrenal for assessment of metastasis.[1] The present case highlights the utility of EUS for diagnosing lung tumours at inaccessible sites. A recent multicentric study from Italy reported the efficacy and safety of EUS-guided tissue sampling as a minimally invasive procedure for the diagnosis and staging of peri-oesophageal parenchymal lung lesions.[2] However, transoesophageal FNA from lung mass may be rarely associated with pneumothorax[3] and haemoptysis.[4] Hence, a check X-ray should be done to rule out pneumothorax before discharging the patient. Keeping in mind the possibilities of complications, EUS-FNA of the lung lesions should be done in centres with the availability of pulmonologist to immediately address the adverse events. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

A case of pancreatic neuroendocrine tumor with amyloid deposition (insulinoma) predicted by rapid on-site evaluation of pancreatic endoscopic ultrasound-guided fine-needle aspiration specimen

A case of pancreatic neuroendocrine tumor with amyloid deposition (insulinoma) predicted by rapid on-site evaluation of pancreatic endoscopic ultrasound-guided fine-needle aspiration specimen

A Case of Extramedullary Plasmacytoma of the Biliary Tract with a Poor Prognosis

Extramedullary plasmacytoma (EMP) is a rare disease consisting of the presence of monoclonal plasma cells in tissues other than the bone. Most EMPs are located in the head and neck region. We present an extremely rare case of an EMP originating from the biliary tract in a 76-year-old male. This is the fifth report of a primary EMP arising from the biliary tract. He was diagnosed with jaundice, and he was referred for an additional examination. Abdominal ultrasonography revealed a tumor in the gallbladder and bile ducts, and a bile duct biopsy was performed via endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). The pathological and immunohistochemical examination revealed that the tumor was a plasmacytoma originating in the biliary tract. Although endoscopic biliary drainage was performed, the bile duct infection was not well controlled due to obstructive jaundice caused by the tumor. Furthermore, the bleeding from the tumor during chemotherapy was uncontrolled. Pancreaticoduodenectomy and cholecystectomy were performed to control the infection and bleeding. Although chemotherapy was continued after surgery, the tumor of the intrahepatic bile duct enlarged. He died seven months after the diagnosis because of the treatment-resistant tumor.

Pancreatic Cystic Lesions: A Focused Review on Cyst Clinicopathological Features and Advanced Diagnostics.

Macroscopic, endomicroscopic, and histologic findings and correlation are an integral part of the diagnostic evaluation of pancreatic cystic lesions (PCLs), as complementing morphologic features seen by different specialties are combined to contribute to a final diagnosis. However, malignancy risk stratification of PCLs with worrisome features can still be challenging even after endoscopic ultrasound guided-fine needle aspiration (EUS-FNA) with cytological evaluation. This review aims to summarize cyst clinicopathological features from the pathologists' perspective, coupled with knowledge from advanced diagnostics-confocal laser endomicroscopy and cyst fluid molecular analysis, to demonstrate the state-of-art risk stratification of PCLs. This review includes illustrative photos of surgical specimens, endomicroscopic and histologic images, and a summary of cyst fluid molecular markers.

Endoscopic ultrasound-guided gallbladder endoscopic mucosal resection: a pilot porcine study

Introduction Endoscopic ultrasound (EUS)-guided natural orifice transluminal gallbladder polypectomy provides a minimally invasive alternative to cholecystectomy. The study aimed to investigate the feasibility and safety of protocol for gallbladder endoscopic mucosal resection (gEMR) under EUS guidance using a porcine model. Material and methods Fifteen Bama mini pigs were randomly divided into the control (CG, n = 3) and experimental (EG, n = 12) groups. EUS-guided fine needle aspiration was performed in the CG and used to establish a gallbladder pathway for polyp resection under EUS guidance in the EG. Procedural safety was evaluated using routine blood and biochemical tests, microbial bile cultures, histopathological tests, and enzyme-linked immunosorbent assays for inflammatory adhesion factors. Results EUS-guided metal stents were successfully deployed in all 12 pigs. Two cases of stent displacement occurred postoperatively, and one pig died of infectious peritonitis on the first day after stent implantation. In 11 surviving experimental animals, mature gallbladder paths were formed at 7–14 days after gastro-cholecystostomy, through which gEMR of gallbladder polyps was successfully performed. There were no significant changes in levels of inflammatory and adhesion factors during the postoperative process. Conclusions EUS-gEMR may be a safe and effective minimally invasive treatment approach for gallbladder polyps.

Quantitative contrast-enhanced endoscopic ultrasound in pancreatic ductal adenocarcinoma and pancreatic neuroendocrine tumors: can we predict survival using perfusion parameters? A pilot study.

Contrast-enhanced harmonic endoscopic ultrasound (CEH-EUS) parameters may be used to predict prognosis of pancreatic ductal adenocarcinoma (PDAC) and pancreatic neuroendocrine tumors (pNET). The aim of this study was to investigate the association between several perfusion parameters on CEH-EUS performed before treatment and survival outcome in patients with PDAC or pNET. Thirty patients with PDAC or pNET who underwent CEH-EUS and EUS-guided fine needle aspiration (EUS-FNA) were included. Quantitative analysis of tumor vascularity was performed using time-intensity curve (TIC) analysis-derived parameters, obtained from processing CEH-EUS recordings with a commercially available software (VueBox). Cox proportional hazards models were used to determine associations with survival outcome. Median overall survival (OS) for PDAC patients was 9.61 months (95% CI: 0.1-38.7) while the median OS for pNET patients was 15.81 months (95% CI: 5.8-24.75. In a multivariate model for OS, a lower peak enhancement (HR=1.76, p=0.02) and a lower wash-in area under the curve (HR=1.06, p=0.001) were associated with worse survival outcome for patients with PDAC. CEH-EUS parameters may be used as a surrogate to predict PDAC aggressiveness and survival before treatment. After validation by large-scale studies, CEH-EUS perfusion parameters have the potential to be used in pretreatment risk stratification of patients with PDAC and in evidence-based clinical decision support.

Interobserver Agreement among Cytopathologists in False-Negative Cases by Cytological Diagnosis with Endoscopic Ultrasound-Guided Fine Needle Aspiration in Solid Pancreatic Lesions

Introduction: Early detection and accurate pathological assessment are critical to improving prognosis of pancreatic cancer. EUS has been widely used in diagnosing pancreatic lesions and can obtain histological diagnosis by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). However, comprehensive assessment of the interobserver agreement (IOA) among cytopathologists evaluating EUS-FNA specimens is still limited. Therefore, this study evaluated IOA among cytopathologists for EUS-FNA specimens of solid pancreatic lesions, especially in false-negative cases of cytological diagnosis and analyzed the factors that influence cytological diagnosis of EUS-FNA so as to improve the diagnostic efficiency of EUS-FNA. Methods: We retrieved EUS-FNA samples of pancreatic solid lesions from 2017 to 2021 and collected their clinical/cytological data. Two cytopathologists independently reviewed these cases using a quoted, novel standardized cytology scoring tool. Ultimately, we calculated IOA among cytopathologists and performed a binary logistic regression analysis to evaluate factors influencing the cytological diagnosis of EUS-FNA. Results: 161 patients were included, and 60 cases with a clinical diagnosis of pancreatic cancer but a cytological diagnosis of benign and atypical constituted the false-negative group. IOAs for cytological diagnosis of overall patients and the false-negative group were in perfect/moderate agreement with Kendall’s W values of 0.896 and 0.462, respectively. The number of diagnostic cells in the scoring tool had the highest level of agreement (κ = 0.721) for overall patients. There was at best moderate agreement on other quantity and quality parameters for both all cases and false-negative group. Logistic regression analysis showed the number of diagnostic cells (OR = 6.110, p < 0.05) and amount of blood (OR = 0.320, p < 0.05) could influence cytological diagnosis. Conclusions: The false-negative rate of our study as high as 37.26% (60/161) is mainly related to strict standards of cytopathologists, and their ability to standardize pancreatic cytology is still improving. Suboptimal agreement among cytopathologists for cytological diagnosis and the number of diagnostic cells may be associated with the occurrence of false-negative diagnosis. Further regression analysis confirmed that the number of diagnostic cells and obscuring blood were important factors in cytological diagnosis. Therefore, refinement of cytological diagnostic criteria, standardization of specimen quality evaluation, and training of cytopathologists may improve the agreement of cytopathologists, thus improving the repeatability of cytological diagnosis and reducing the occurrence of false-negative events.

P53 immunolabeling in EUS-FNA biopsy can predict low resection rate and early recurrence in resectable or borderline resectable pancreatic cancer treated with neoadjuvant therapy.

KRAS, P16, TP53, and SMAD4/DPC4 mutations are common in pancreatic ductal adenocarcinoma (PDAC). The study aimed to evaluate the association between gene mutations in pre-treatment endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) samples and clinical outcomes of patients with PDAC. There were 43 patients with resectable (R) PDAC and 41 patients with borderline resectable (BR) PDAC. CDKN2A/p16, TP53, and SMAD4/DPC4 were evaluated through immunohistochemistry (IHC) of pretreatment EUS-FNA (n=84) and resected specimens (n=71). All patients received neoadjuvant therapy. IHC of EUS-FNA specimens revealed p16 loss in 61 (73%), abnormal p53 in 61 (73%), and Smad4 loss in 38 (45%) patients. Abnormal p53 was associated with a lower resection rate (p=.017). Abnormal p53 and Smad4 loss were associated with recurrence within 6 months post-pancreatectomy (p=.03, p=.03, respectively). Univariate Cox regression analysis was conducted to reveal that abnormal p53 (p=.07), p16 loss and abnormal p53 (p=.04), and Smad4 and p16 loss (p=.03) were associated with poor prognosis. Pre-treatment abnormal labeling of p53 in EUS-FNA specimen was associated with a lower resection rate and an early recurrence in R or BR PDAC cases.

Retroperitoneal liposarcoma with pancreatic metastasis and gastric cancer: a case report.

On computed tomography scanning, a 63-year-old man with vomiting and anorexia was discovered to have a mass in the pancreatic body and a retroperitoneal mass extending to the right lobe of the liver. An esophagogastroduodenoscopy revealed an advanced gastric carcinoma in the middle gastric body, and a biopsy specimen revealed a poorly differentiated adenocarcinoma. The pancreatic and retroperitoneal masses were considered metastatic lesions of gastric cancer, and a biopsy was taken from the pancreatic lesion using endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). The histology of the EUS-FNA pancreatic specimen revealed atypical spindle-shaped cells and increased stromal collagen fibrosis, and liposarcoma was considered. Conversely, a percutaneous ultrasound-guided biopsy was taken for the retroperitoneal lesion, and the histology revealed that it was a dedifferentiated liposarcoma. On the basis of histopathological and imaging findings, the retroperitoneal liposarcoma was identified as the primary lesion, the pancreatic lesion as a metastasis of the primary liposarcoma, and the gastric carcinoma as an independent tumor. As far as we know, there have only been three reports of metastatic pancreatic liposarcoma diagnosed via EUS-FNA. In this case, the patient also had gastric cancer, and EUS-FNA was helpful in differentiating metastatic pancreatic tumors from gastric cancer.

Curative surgery for primary squamous cell carcinoma of the liver: a rare case study.

Primary squamous cell carcinoma (SCC) of the liver is an extremely rare disease with a very poor prognosis. An 83-year-old woman was referred to our hospital with left abdominal pain. Laboratory data showed mildly elevated C-reactive protein and biliary enzymes. The tumor markers carcinoembryonic antigen, alpha-fetoprotein, and carbohydrate antigen 19-9 were within normal ranges. Contrast-enhanced computed tomography revealed a 60mm-sized low-density mass with poor contrast enhancement located in the lateral segment of the liver. The tumor showed low signal on T1-weighted magnetic resonance imaging (MRI) and high signal on T2-weighted MRI. The cytology of bile juice showed no malignant findings. Endoscopic ultrasound-guided fine-needle aspiration biopsy was performed, which was suggestive of primary hepatic SCC. Tumor markers cytokeratin 19 fragment (CYFRA) and SCC-related antigen were elevated, at 25.2ng/mL and 14.7ng/mL, respectively. Left lobectomy and hilar lymph node dissection were performed. One month after surgery, the tumor marker values showed a marked decrease of 1.8ng/mL for CYFRA and 0.3ng/dL for SCC-related antigen. The patient has been without recurrence for more than one and half year postoperatively. SCC-related antigen and CYFRA were markedly decreased after tumor resection in this case, which may suggest their utility as tumor markers for SCC of liver origin.

Role of Endoscopy in Esophageal Tuberculosis: A Narrative Review

Esophageal tuberculosis (ET) is a rare infectious disease of the gastrointestinal tract. Awareness of ET is deficient due to its low incidence. Unexplained dysphagia and upper gastrointestinal bleeding are the most common symptoms of ET. The prognosis is generally good if patients are diagnosed properly and receive anti-tubercular treatment promptly. However, ET is difficult to differentiate from other diseases. Endoscopic techniques such as esophagogastroduodenoscopy (EGD), endoscopic ultrasonography (EUS), contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS), elastography, and endoscopic ultrasound--guided fine-needle aspiration (EUS-FNA) improve the diagnosis of ET. Thus, the characteristics of ET and other difficult-to-detect diseases according to EGD and EUS were summarized. Intriguingly, there is no literature relevant to the application of CH-EUS and elastography in ET. The authors' research center was first in introducing CH-EUS and elastography into the field of ET. The specific manifestation of ET based on CH-EUS was discovered for the first time. Correlative experience and representative cases were shared. The role of endoscopy in acquiring esophageal specimens and treatment for ET was also established. In this review, we aim to introduce a promising technology for the diagnosis and treatment of ET.

Endoscopic Ultrasound Guided Fine Needle Aspiration versus Endoscopic Ultrasound Guided Fine Needle Biopsy for Pancreatic Cancer Diagnosis: A Systematic Review and Meta-Analysis.

One of the most effective diagnostic tools for pancreatic cancer is endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) or biopsy (EUS-FNB). Several randomized clinical trials have compared different EUS tissue sampling needles for the diagnosis of pancreatic cancer. To compare the diagnostic accuracy of EUS-guided FNA as EUS-FNB needles for the diagnosis of pancreatic cancer using a systematic review and meta-analysis. A literature review with a meta-analysis was performed according to the PRISMA guide. The databases of PubMed, Cochrane and Google Scholar were used, including studies published between 2011-2021 comparing the diagnostic yield (diagnostic accuracy or probability of positivity, sensitivity, specificity, predictive value) of EUS-FNA and EUS-FNB for the diagnosis of pancreatic cancer. The primary outcome was diagnostic accuracy. Random effect models allowed estimation of the pooled odds ratio with a confidence interval (CI) of 95%. Nine randomized control trials were selected out of 5802 articles identified. Among these, five studies found no statistically significant difference between the EUS-FNA and EUS-FNB, whereas the other four did. The meta-analysis found EUS-FNB accuracy superior to EUS-FNA for the diagnosis of pancreatic cancer with a pooled odds ratio of 1.87 (IC 95%: 1.33-2.63). As compared to EUS-FNA, EUS-FNB seems to improve diagnostic accuracy when applied to suspicious pancreatic lesions.

Pancreatic duct lavage cytology combined with a cell-block method for patients with possible pancreatic ductal adenocarcinomas, including pancreatic carcinoma in situ.

This study aimed to clarify the efficacy and safety of pancreatic duct lavage cytology combined with a cell-block method (PLC-CB) for possible pancreatic ductal adenocarcinomas (PDACs). This study included 41 patients with suspected PDACs who underwent PLC-CB mainly because they were unfit for undergoing endoscopic ultrasonography-guided fine needle aspiration. A 6-Fr double lumen catheter was mainly used to perform PLC-CB. Final diagnoses were obtained from the findings of resected specimens or clinical outcomes during surveillance after PLC-CB. Histocytological evaluations using PLC-CB were performed in 87.8% (36/41) of the patients. For 31 of the 36 patients, final diagnoses (invasive PDAC, 12; pancreatic carcinoma in situ, 5; benignancy, 14) were made, and the remaining five patients were excluded due to lack of surveillance periods after PLC-CB. For 31 patients, the sensitivity, specificity, and accuracy of PLC-CB for detecting malignancy were 94.1%, 100%, and 96.8%, respectively. In addition, they were 87.5%, 100%, and 94.1%, respectively, in 17 patients without pancreatic masses detectable using endoscopic ultrasonography. Four patients developed postprocedural pancreatitis, which improved with conservative therapy. PLC-CB has an excellent ability to detect malignancies in patients with possible PDACs, including pancreatic carcinoma in situ.

Is antibiotic prophylaxis necessary after endoscopic ultrasound-guided fine-needle aspiration of pancreatic cysts?

Current society guidelines recommend antibiotic prophylaxis for 3 to 5 days after endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic cystic lesions (PCLs). The overall quality of the evidence supporting this recommendation is low. In this study, we aimed to assess cyst infection and adverse event rates after EUS-FNA of PCLs among patients treated with or without postprocedural prophylactic antibiotics. We retrospectively reviewed all patients who underwent EUS-FNA of PCLs between 2015 and 2019 at two large-volume academic medical centers with different practice patterns of postprocedural antibiotic prophylaxis. Data on patient demographics, cyst characteristics, fine-needle aspiration technique, periprocedural and postprocedural antibiotic prophylaxis, and adverse events were retrospectively extracted. A total of 470 EUS-FNA procedures were performed by experienced endosonographers for the evaluation of PCLs in 448 patients, 58.7% of whom were women. The mean age was 66.3±12.8 years. The mean cyst size was 25.7±16.9 mm. Postprocedural antibiotics were administered in 274 cases (POSTAB+ group, 58.3%) but not in 196 cases (POSTAB- group, 41.7%). None of the patients in either group developed systemic or localized infection within the 30-day follow-up period. Procedure-related adverse events included mild abdominal pain (8 patients), intra-abdominal hematoma (1 patient), mild pancreatitis (1 patient), and perforation (1 patient). One additional case of pancreatitis was recorded; however, the patient also underwent endoscopic retrograde cholangiopancreatography. The incidence of infection after EUS-FNA of PCLs is negligible. Routine use of postprocedural antibiotics does not add a significant benefit.

Endoscopic Ultrasound-Guided Fine Needle Aspiration of Solid Pseudopapillary Neoplasm of the Pancreas in a Male Patient: A Rare Report

Abstract Introduction/Objective Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare pancreatic tumor with low malignant potential composed of poorly cohesive epithelial cells forming solid and pseudopapillary structures. It develops almost exclusively (90%) in young females (mean age: 28 years, range: 7-79 years), while it rarely develops in men (mean age: 35 years, range: 25-72 years). Methods/Case Report Herein we report an unusual presentation of SPN in a 59-year-old male who presented with severe nausea, vomiting, right upper quadrant pain, and weight loss. Computed tomography imaging revealed a large pancreatic head/uncinate process mass. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) biopsies showed abundant monomorphic cuboidal tumor cells arranged in loosely cohesive groups and singly dispersed cells. A few tumor cells are arranged in multiple layers around vascular structures expanded by metachromatic hyaline material. The tumor cells have thin cytoplasm, indistinct cell borders, round to oval nuclei, finely dispersed chromatin, and indistinct nucleoli. No mitosis, tumor necrosis, or other high-grade features are identified. Immunohistochemical stains are performed on cell block material and the tumor cells are positive for beta-catenin (nuclear), cyclin D1, vimentin, CD10, synaptophysin, and CD56, and negative for DOG-1, tryptase, and AE1/AE3. Ki-67 proliferative index is less than 2% in tumor cells. The cytomorphologic features and immunoreactivity are diagnostic of solid pseudopapillary neoplasm. We diagnosed SPN preoperatively by EUS-FNA using cytopathologic and immunochemical characteristics, which are very helpful to differentiate SPN from acinar cell carcinoma, neuroendocrine tumor, pancreatoblastoma, or other pancreatic tumors. Results (if a Case Study enter NA) NA Conclusion EUS-FNA can be used as a gold standard method to characterize and diagnose SPN preoperatively and help to guide clinical management.

The role of rectal endoscopic ultrasonography plus fine needle aspirartion and fine needle biopsy in pelvic masses.

The diagnostic role of endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) and fine needle biopsy (FNB) of pelvic masses has not been well established. We aimed to evaluate the diagnostic accuracy of EUS plus FNA/FNB in suspected local recurrence of pelvic masses. All consecutive patients with a history of lower gastrointestinal and pelvic mass undergone EUS-FNA/FNB were included in the study. In total 34 patients who underwent EUS-guided FNA or FNB of a perirectal mass were enrolled. The sampled lesion was a mass in 22 patients (64.7%) and a lymph node in 10 patients (29.4%). The univariate logistic regression analysis for diagnostic accuracy showed lesion size as a significant predictor of diagnostic accuracy [odds ratio (OR), 1.61; 1.08-2.27; P = 0.02]. Diagnostic sensitivity was 100% (71.5-100%) with EUS-FNB and 75% (34.9-96.8%) with EUS-FNA ( P = 0.12); specificity was 100% in both groups ( P = 1.0). Sample adequacy was 94.1% in the whole cohort, with 20/20 adequacy rate (100%) in the EUS-FNB group and 12/14 (85.7%) in the EUS-FNA group ( P = 0.28). This is the first study demonstrating the diagnostic yield of EUS plus FNA/FNB in patients with pelvic masses comparing the two needles. Our results highlight the relevance of this technique, especially in undefined masses during oncological follow-up.

Cytopathology of rare gastric mesenchymal neoplasms: A series of 25 cases and review of literature.

Gastrointestinal stromal tumour (GIST) is the most common mesenchymal neoplasm arising in the stomach. However, a number of other rare mesenchymal neoplasms do occur at this anatomic site, which often presents a diagnostic challenge for cytopathologists on endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Our study aims to selectively present the clinico-radiological and cytopathological characteristics of these rare "non-GIST" neoplasms, as well as their differential diagnoses. We performed a 20 year retrospective search in the cytopathology database of our two large medical institutions for non-GIST mesenchymal neoplasms arising in the stomach and diagnosed on EUS-FNA. Data regarding the patients' demographics and radiological findings were analysed. All available cytopathology specimens were reviewed. The cytomorphological characteristics and the accompanying immunohistochemical stains, when available, were subsequently analysed. Twenty-five cases of gastric mesenchymal tumours were selectively included in the study after excluding all cases of GIST (n=113) diagnosed on FNA. These cases included 10 leiomyomas (40%), eight schwannomas (32%), five glomus tumours (20%), one perivascular epithelioid cell neoplasm, and one desmoid tumour. The specimen cellularity was variable and ranged from hypocellular to highly cellular. Most smears were composed of spindle cells with a few showing epithelioid morphology. Cell blocks were available in 20 cases and a range of immunohistochemical ancillary studies were performed. DOG-1, c-KIT, smooth muscle actin (SMA), and S100-protein were the most common immunomarkers done. Our study highlights important cytomorphological characteristics of rare mesenchymal neoplasms arising in the stomach. In the appropriate clinical setting and with the help of immunohistochemistry, an accurate diagnosis of these neoplasms can be achieved.

KRAS Mutation Testing on Endoscopic Ultrasound-Guided Fine-Needle Aspiration Samples Improves the Diagnostic Accuracy of Pancreatic Cancer.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) cytology was one of the investigations for pancreatic masses. While the specificity approached 100%, its sensitivity remained low because of high rate of indeterminate and false-negative results. Meanwhile, KRAS gene was frequently mutated in up to 90% of pancreatic ductal adenocarcinoma and its precursor lesions. This study aimed to determine whether KRAS mutation analysis could improve the diagnostic sensitivity in EUS-FNA samples for pancreatic adenocarcinoma. The EUS-FNA samples from patients with a pancreatic mass obtained between January 2016 and December 2017 were reviewed retrospectively. The cytology results were classified as malignant, suspicious for malignancy, atypical, negative for malignancy, and nondiagnostic. KRAS mutation testing was performed using polymerase chain reaction followed by Sanger sequencing. A total of 126 EUS-FNA specimens were reviewed. The overall sensitivity and specificity by cytology alone were 29% and 100%, respectively. When KRAS mutation testing was performed in cases with indeterminate and negative cytology, the sensitivity increased to 74.2%, and the specificity remained at 100%. KRAS mutation analysis, especially when performed in cytologically indeterminate cases, improves the diagnostic accuracy for pancreatic ductal adenocarcinoma. This may reduce the need to repeat invasive EUS-FNA for diagnosis.